In neuroscientific circles, it is simply commonsense physicalism that the brain conducts business on its own. It doesn’t need a further, non-physical agent to orchestrate the dauntingly complex operations that constitute awareness, cognition, and control of behavior. Nevertheless, it’s also become clear that for us to successfully navigate the world, the brain must conjure a stable sense of a self, acting within an environment represented as distinctly non-self. Even though there’s no one in charge of its operations, the brain generates a strong intuition of personal agency, borne out by the obvious fact that persons accomplish all sorts of things in all manner of ways.

Curiously, the sense of self and agency bequeathed us by the brain has, in combination with the legacy of Cartesian dualism, generated the widespread belief (at least in the West) that there is indeed a non-physical controller which is the true self. The functionally necessary self/world distinction has been overlaid with, or misinterpreted as, the metaphysically dubious and functionally otiose proposition that persons, as Harvard psychologist Daniel Wegner puts it, “cause themselves to behave.” Folk wisdom has it that from some internal vantage point, imagined to be something over and above the brain, we consciously will our actions – behavior is more than the deterministic outcome of neural and muscular mechanisms.

In The Illusion of Conscious Will, Wegner sets out to deconstruct, largely from an experimental psychological perspective, this sense of conscious willing. His thesis is that our feeling of will doesn’t reflect the underlying causes of behavior, rather it’s an “emotion of authorship” that usefully tags actions as ours, not someone else’s. This is very much in line with neuroscientific and cognitive-behavioral accounts of the functional necessity of having a robust self-representation. The sense of will more or less accurately tracks who (me or somebody else) did what, so that persons can successfully manage social contingencies.

Wegner says, plausibly enough, that the feeling that we consciously will action – that an act is ours – ordinarily arises whenever conscious intentions precede behavior: “We tend to see ourselves as the authors of an act primarily when we have experienced relevant thoughts about the act at an appropriate interval in advance.” Our folk-psychological theory of action interprets this regular sequencing of intention and behavior as causal, with the conscious, mental intention (the will) driving the physical effect (behavior). But, Wegner says, the actual causal story behind human behavior involves a “massively complicated set of mechanisms,” what he calls the “empirical will,” that produces both intention and action. Since we aren’t in a position to observe or understand these mechanisms, instantiated as they are by the complex neural systems of our brain and body, we construct an explanation involving the experienced, phenomenal will: we, as conscious, mental, willing agents, simply cause our behavior.

Wegner’s book is a comprehensive, well-documented, and nicely written account of how the feeling of will might be generated, both in terms of neural processes and in terms of the conditions of behavior. (Wegner is, in fact, occasionally hilarious in some of his understated one-liners, which he could easily take on the road should he tire of his day job.) Manipulate the perception and timing of intentions and behavior, and the sense of owning action will change as well, and in predictable ways. Surveying data on neurological deficits, phantom limb phenomena (Ramachandran), direct brain stimulation (Penfield, Delgado), and the neural systems underlying voluntary behavior, Wegner concludes that “the experience of will many not be very firmly connected to the processes that produce action, in that whatever creates the experience of will may function in a way that is only loosely coupled with the mechanisms that yield action itself.” That the phenomenal will might be an “add-on” is reinforced by a review of Libet’s well-known findings that the consciousness of initiating voluntary movement is reliably preceded by the (unconscious) onset of a movement readiness potential. Such evidence suggests that consciousness, and therefore conscious will, can hardly function as the mental initiator or controller of action it is often taken to be.

A good deal of Wegner’s book is devoted to explaining various distortions and outright abrogations of the feeling of conscious agency, as for instance in hypnosis. Those under the hypnotic suggestion that their arms are getting lighter don’t feel as if they are lifting their arms; instead, they feel that the arm rises involuntarily, or is controlled by the hypnotist. Likewise, those using a Ouija board discover that the planchette under their fingers seems to move on its own, even though the messages it spells out can only come, ultimately, from the participants. Dowsers looking for water report that the dowsing rod moves autonomously in their hands, relaying unseen forces. In these and dozens of other cases Wegner analyzes, the perceived sense of intentional agency shifts temporarily from the self to someone else (the hypnotist), or even something else (the planchette, the dowsing rod). We seem driven to impute willful control, even if the will isn’t ours.

Usually, though, we feel very much in control, and indeed Wegner points out that we are experts at deluding ourselves that we are ideal agents, always aware of what we’re doing, and why. We routinely generate rationalizations for acting in ways we swore we never would. We can even concoct intentions after having acted, but have it seem as if the intentions came first. Rather than admit ignorance about the causes of behavior, which aren’t always obvious, we confabulate stories that keep the self in the driver’s seat. Such feats of image maintenance, Wegner suggests, testify to the importance of the ideal of conscious will.

But why precisely are we so attached to the notion of being ideal conscious willers, always in control? Part of the answer, as noted above, is that the feeling of conscious agency functions to assign authorship to behavior, a necessity in negotiating the social world of action. And as philosopher Daniel Dennett has suggested, taking the “intentional stance” with regard to other people – supposing they are acting on the basis of consciously appreciated reasons – is a very reliable strategy for predicting their behavior.

But there may be more at stake that reinforces the illusion of total conscious control, namely the deeply ingrained, folk-metaphysical assumption that human beings possess contra-causal free will. If, as many suppose outside the scientific community, we are free to act in ways that are non-mechanistic, indeed, that defy mechanism, then this supposition invites a particularly strong interpretation of the sense of voluntary action: that we act for no cause but our self-generated will. But the causal power of this will is exactly what Wegner painstakingly exposes as an illusion.

In his last chapter, “The Mind’s Compass,” Wegner touches on the conflict between the assumption of free will and scientific explanations of behavior, arguing that although the sense of willing shouldn’t be confused with agency, it’s nevertheless an important indicator of agenthood. The feeling of conscious will is a reliable, if not infallible, guide that an action is indeed our action, one that resulted from our character, motives, concerns, and plans. Agents, even if they don’t cause themselves to behave, still have causal powers to make things to happen, and according to what philosophers call compatibilist accounts of moral responsibility, we are justified in holding them responsible. Not because such agents could have done otherwise in exactly the same molecule-for-molecule situation (they couldn’t), or because they created themselves in some metaphysically obscure sense (they didn’t), but because holding them responsible works to shape responsible, normative behavior. Such moral responsibility, although not everything diehard free willers might want, is compatible with our being fully caused creatures.

Although Wegner doesn’t explicitly endorse this sort of compatibilism, or delve too deeply into the philosophical morass of free will, he acknowledges (as any scientist should) that the real causal story behind human behavior is likely deterministic. We shouldn’t try to make free will do what he calls “determinism’s causal job,” but instead accept that, as an emotion of authorship, the feeling of doing plays an important role in deciding questions of voluntary agency.

Despite his genial, unpretentious style, some may find Wegner’s message distinctly unpalatable, since it challenges long-held assumptions about the causal role of will as the necessary foundation for moral responsibility. Yet it is only by coming to terms with what science tells us about human agency that we can remain, in the long run, psychologically whole. Wegner gives us important notice of the times to come by revealing the contours of a leaner, empirically validated self, whose sense of efficacy can be deconstructed without undermining our actual causal powers or the basis for our moral practices. It’s even possible that, by penetrating the illusion of conscious will, we might become more enlightened agents.